Final answer:
A nerve net is a simple, decentralized arrangement of nerve cells found in some organisms like jellyfish, where neurons spread throughout the body to control functions without a centralized brain. It contrasts with more complex nervous systems that have central and peripheral divisions with a brain and connecting nerves.
Step-by-step explanation:
The concept of a nerve net relates to the organization of nervous systems in certain simple organisms, such as cnidarians like jellyfish. In a nerve net, nerve cells are distributed throughout the organism's body rather than being centralized into a brain or organized along a central nervous system. These nerve cells are capable of conducting signals in multiple directions, leading to a more diffused control of the organism's body and functions. More complex organisms may have a central nervous system (CNS) which includes a brain and spinal cord, or a peripheral nervous system (PNS) that extends throughout the body. The PNS connects to the CNS using nerves, which are bundles of axons that carry signals to and from various parts of the body. In contrast to this, the nerve net consists of a decentralized array of interconnected neurons that work together to control bodily functions but without a central controlling organ like the brain. A nerve net can be found in certain animals exhibiting radial symmetry, such as cnidarians, and is a simple form of nervous system organization. It consists of neurons that are connected to form a network spread out across the body, thus enabling these creatures to respond to environmental stimuli in a coordinated fashion despite the absence of a centralized brain structure.